Window screen



FIG. 1 is a Perspective view of a window screen showing my new design;

FIG. 2 is a Front view thereof;

FIG. 3 is a Back view thereof;

FIG. 4 is a Left-side view thereof;

FIG. 5 is a Right-side view thereof;

FIG. 6 is a Top view thereof;

FIG. 7 is a Bottom view thereof; and,

FIG. 8 is Other Perspective view thereof.

The broken lines are for the purpose of illustrating portions of the article that form no part of the claim. 

CLAIM I claim the ornamental design for a window screen, as shown and described. 